A fire that drew out 110 firefighters and 19 trucks to a factory operated by Samsung Galaxy Note 7 battery supplier, Samsung SDI, was caused by discarded faulty batteries, the company has said.

A “minor fire” broke out Wednesday in a Samsung SDI plant in the northern Chinese city of Tianjin and had to be extinguished, according to local emergency services Reuters reports.

The fire was contained to a part of the site used for waste processing, including faulty batteries. There were no casualties or significant impact on the operations of the plant, although the local fire department was called, said a Samsung SDI spokesperson.

The Wuqing branch of the Tianjin fire department said on Sina Weibo that the “material that caught fire was lithium batteries inside the production workshops and some half-finished products”.

Samsung SDI operates five plants within China, with Tianjin operating as the main manufacturing point for small batteries used in portable electronics, including the ill-fated Galaxy Note 7 that had to be recalled twice and withdrawn from sale leaving Samsung with a $5.3bn (£4.24bn) hole in operating profit.

Samsung SDI said in February that it is has invested approximately 150bn won ($131m) in safety. The Note 7’s fires have caused manufacturers and battery supplies across the globe to double down on testing, with some delaying shipping devices with more advanced batteries in favour of older, inferior but tried and tested designs.

The Samsung Galaxy S8 will be crucial in maintaining the company’s competition with arch rival Apple and newer players such as China’s Huawei. It will launch on or around21 April, have an edge-to-edge infinity screen, iris scanner and waterproof design, according to insiders.